SKIN DEVA 20% Vitamin C Serum for Face with Vitamin E Plus Ferulic Acid Skincare Water Based 1 fl oz 30 ML Rejuvenates Skin to Fresh & Neutralizes Free Radicals to Brighten Even Vitamin Serum

•When Freshly manufactured serum is white liquid then by the time goes it changes color to transparent water and then after sometime it change to yellowish , its completely ok to use it , Yellow doesn't mean the serum is oxidized . Its natural process of L ascorbic base Vitamin C. *Vitamin E may exacerbate an already oil-prone condition. To be sure this formulation is right for you, modify the use of serum by gradually incorporating it into your routine, or by using fewer drops until the skin has become acclimated to it. We recommend to keep it in refrigerator so it keep long last and give better effective result” as nature of this product you might see yellow color change in liquid but it doesn’t mean it oxidize or expire